For many applications buffer circuits must be operable for various ranges of input voltages. For example, applications commonly exist when a buffer circuit must accept both TTL voltage levels and MOS voltage levels. Previously, multiple voltage level buffer circuits requiring circuitry dedicated for each voltage level have been used. Such circuits require multiple inputs and utilize circuitry which detects an input voltage level. Others have used a trinary input buffer which is also known as a tri-state device. Trinary input buffers however typically consume power when in a static state. Other buffer circuits which accept multiple level input voltages require a separate pin in an integrated circuit package which is used to indicate what level to detect.